Static Quiz 19 May 2022 (Geography)

Ans;- c) Only 1,2 and 4

Explanation;-

• Except the Deltas all are the Erosional Features created By Rivers, Deltas are the Depositional Features of Rivers, even the Ox-bow has both the deposition and erosion but more appropriate option will be C ,because Delta is absolutely a depositional feature of river.

• A V-valley is formed by erosion from a river or stream over time. It is called a V-valley as the shape of the valley is the same as the letter “V”.
• As the river erodes downwards the sides of the valley are exposed to freeze-thaw weathering which loosens the rocks (some of which will fall into the river) and steepens the valley sides.

• An interlocking spur, also known as an overlapping spur, is one of any number of projecting ridges that extend alternately from the opposite sides of the wall of a young, V-shaped valley down which a river with a winding course flows.

• A river delta is a landform created by deposition of sediment that is carried by a river as the flow leaves its mouth and enters slower-moving or stagnant water.
• This occurs where a river enters an ocean, sea, estuary, lake, reservoir, or (more rarely) another river that cannot carry away the supplied sediment.

• Sometimes, because of intensive erosion action, the outer curve of a meander gets accentuated to such an extent that the inner ends of the loop come close enough to get disconnected from the main channel and exist as independent water bodies called as oxbow lakes.
• These water bodies are converted into swamps in due course of time.

Ans;- d) All of the above

Explanation;-

• An alluvial fan is an accumulation of sediments shaped like a section of a shallow cone, with its apex at a point source of sediments, such as a narrow canyon emerging from an escarpment.

• A floodplain or flood plain or flood-plain is an area of land adjacent to a stream or river which stretches from the banks of its channel to the base of the enclosing valley walls, and which experiences flooding during periods of high discharge.

• Deltas are wetlands that form as rivers empty their water and sediment into another body of water, such as an ocean, lake, or another river. Although very uncommon, deltas can also empty into land. A river moves more slowly as it nears its mouth, or end.

• A natural levee has a long, broad, low shape and is composed of sand and coarse silt, which was built by a stream on its flood plain and along both sides of its channel especially in time of flood when water overflowing the normal banks is forced to deposit the coarsest part of its load.

Ans;- d) Ait

Explanation;-

• Ait is the Fluvial landform, remaining are not.

• Fluvial landforms are those generated by running water, mainly rivers. The term fluvial derives from the Latin word fluvius that means river.

• An ait  is a small island. It is especially used to refer to river islands found on the River Thames and its tributaries in England.

• Aits are typically formed by the deposit of sediment in the water, which accumulates over a period of time.

• An esker, eskar, eschar, or os, sometimes called an asar, osar, or serpent kame, is a long, winding ridge of stratified sand and gravel, examples of which occur in glaciated and formerly glaciated regions of Europe and North America.

• A cirque is an amphitheatre-like valley formed by glacial erosion. Alternative names for this landform are corrie and cwm. A cirque may also be a similarly shaped landform arising from fluvial erosion. The concave shape of a glacial cirque is open on the downhill side, while the cupped section is generally steep.

• An arête is a thin, crest of rock left after two adjacent glaciers have worn a steep ridge into the rock. A horn results when glaciers erode three or more arêtes, usually forming a sharp-edged peak. Cirques are concave, circular basins carved by the base of a glacier as it erodes the landscape.

Ans;- c) Alluvial Fans

Explanation;-

• An alluvial fan is a triangle-shaped deposit of gravel, sand, and even smaller pieces of sediment, such as silt, this sediment is called alluvium. 
• Alluvial fans are usually created as flowing water interacts with mountains, hills, or the steep walls of canyons.
• Alluvial fans and bajadas are often found in deserts, where flash floods wash alluvium down from nearby hills.
• They can also be found in wetter climates, where streams are more common. Alluvial fans are even found underwater.
• Both deltas and alluvial fans are types of depositional land forms formed by flowing rivers. 
• Alluvial fans are formed at foothills where streams flowing from higher level break into foot slope plains of low gradient whereas deltas are formed near mouth of streams where it meets seas or stagnant water bodies.

Ans;- d) None of the above

Explanation;-

• All are incorrectly matched.

• Hydraulic action It is a mechanical process, in which the moving water current flows against the banks and bed of a river, thereby removing rock particles.
• Some of the water splashes against the river banks and surges into cracks and crevices. This helps to disintegrate the rocks. The river water picks up the loose fragments from its banks and bed and transports them away.

• Attrition this is a form of fluvial erosion in which the bed load is eroded by itself due to wear and tear of the transported material when they roll and collide into one another. The coarser boulders are broken down into smaller stones and pebbles.

• Corrosion or solution this is the chemical or solvent action of water on soluble or partly-soluble rocks with which the river comes into contact. For example, calcium carbonate in limestone is easily dissolved and removed in solution.